Alternator, water pump, crankshaft belt alignment?

[Ian_Edwards]

I’m currently installing a new alternator, but I’m concerned that the new alternator doesn’t line-up with the water pump and crankshaft pulleys.
The engine is a Yanmar 4JH4E, from 2007, with about 2,000 hrs on the clock.
The pulley’s have been upgraded to a serpentine belt, with an Electro Maax kit.
The new alternator is a Balmar series 6, 120amp unit.
The pulley on the Balmar is a different shape to the pulley on the water pump and the crankshaft, making it difficult if not impossible to use straight edge to line up the faces of the pulleys.
I no longer trust my eyesight to line things up, having had cataract operations and I also ware varifocals, which make things which I know are strain look bent.
The alternator is a saddle mount, and I don’t see an obvious way of adjusting the axial (fore and aft)position of the alternator. The way it is designed, it look as if it should line-up without the need for adjustment.
Any ideas on how to check the alignment, and if it needs adjusting, how that can be achieved.
I found it hard to get decent photo with my mobile, the wide angle lens distorts the perspective.

 

[rotrax]

The Balmar has a sleeve pressed into the lower mount which can move back and forth.

Looks to me as if the adjusting kit has a spacer between the alternator and bracket holding the alternator forward.

I have a 4JH4-HTE. No spacer between the top bracket and alternator. My belt lines up fine, but is the OE type. I use genuine Gates notched belts with no issues. No adjustment needed this season, almost 200 engine hours.

If you take that spacer out, tighten the top bolt the alternator will slide through the bottom sleeve until it is tight against the adjusting bracket.

If you dont use the belt/pulley cover, remove and replace the special bolts with normal bolts of the correct length. Gives better access in a confined space.

 

[Poey50]

I’m currently installing a new alternator, but I’m concerned that the new alternator doesn’t line-up with the water pump and crankshaft pulleys.
The engine is a Yanmar 4JH4E, from 2007, with about 2,000 hrs on the clock.
The pulley’s have been upgraded to a serpentine belt, with an Electro Maax kit.
The new alternator is a Balmar series 6, 120amp unit.
The pulley on the Balmar is a different shape to the pulley on the water pump and the crankshaft, making it difficult if not impossible to use straight edge to line up the faces of the pulleys.
I no longer trust my eyesight to line things up, having had cataract operations and I also ware varifocals, which make things which I know are strain look bent.
The alternator is a saddle mount, and I don’t see an obvious way of adjusting the axial (fore and aft)position of the alternator. The way it is designed, it look as if it should line-up without the need for adjustment.
Any ideas on how to check the alignment, and if it needs adjusting, how that can be achieved.
I found it hard to get decent photo with my mobile, the wide angle lens distorts the perspective.

View attachment 125730

I did a Balmar and serpentine belt upgrade last year and found this article from Rod Collins invaluable.

Marine Alternator Installation - Tips & Tricks - Marine How To

 

[IanCC]

You put a straight edge across a pulley face then measure the distance of the edge of the belt from the straight edge with a pair of deviders.
You shim the pulley on the balmar. Good article on website "marine how to".

 

[jwfrary]

I had to shim the crank pulley on an electromax kit on a 4JH3-DTE.

You'll need to get your 1m steel rule out and compare the alignment.

 

[101chugger]

I asked a similar question recently as the belt on my Beta 14 was producing loads of black dust. On inspection the alternator pulley sat forward of the other two pulleys. On the Beta it’s not possible to adjust the alternator position fore or aft. A knowledgeable friend suggested that I place a steel rule along the pulleys, measure the amount that the alternator sat forward of the other, then shave that amount off the alternator lug that attaches it to the engine. I’ve done that. The alternator casing is aluminium, and so it was the easiest job to use the flat edge of an angle grinder disc to shave 2mm off the alternator lug. It all lines up now. I won’t run the engine until next season as it’s winterised but things look favourable so far. If it doesn’t work I can always make up the space again with a shim washer against the alternator lug. The pictures shop that the pulleys line up after the alternator lug was shaved of 2mm.